In surgery, especially when fitting dental implants, practitioners are often confronted with a requirement for bone material to be used for backfilling. Backfilling ensures good retention of an implant or contributes to the esthetic aspects of the practitioner's work.
In practice, this refers to carrying out bone micrografts.
Self-grafting is recommended to prevent rejection of the graft. To this end, bone is taken from the patient and reimplanted directly during the intervention, with minimum handling.
Practitioners usually attempt to recover as much bone material as possible from the drills and other tools used. This is not always effective, and the volume of bone recovered is not always sufficient.
In some circumstances, if the quantity of bone recovered is insufficient, synthetic bone backfilling materials may be used. Such materials, although developed for this specific purpose, do not guarantee so readily the absence of graft rejection.
During dental surgical interventions, while the practitioner is working in the mouth, an assistant is responsible for aspiration of saliva and debris present in the mouth. This aspiration is effected using canulas connected to the standard suction system of the dentist's chair. Thus, during drilling operations, bone debris are aspirated and lost in the general filtration system of the dentist's chair.
Recovery systems using filters have already been envisaged for increasing the quantity of bone recovered. For example, U.S. Pat. No. 6,299,763 describes a device of this kind, comprising a main body which has an axial cavity passing through it that has a proximal end and a distal end, and comprising a front connector that has an axial passage through it and is fixed to the distal end of the main body. A filter with a filtering wall of generally cylindrical tubular shape may be fitted into the main body and held coaxially therein. An annular cavity is left free around the filter between the cylindrical filtering wall of the filter and the internal lateral faces of the axial main body and the front connector. In the recovery position, a proximal stopper shuts off the proximal end of the filter, and forces the liquid to pass radially through the wall of the filter and then to flow around the stopper to exit via an axial outlet.
In the above device, bone fragments are collected inside the filter during the recovery step, by virtue of aspiration of the fluids from the axial outlet.
The bone must then be recovered. In the above prior art device, this requires separation of the axial main body and the front connector, extraction of the filter and its stopper, and then insertion of the distal end of a scraper piston, removal of the stopper and movement of the scraper piston toward the proximal end to propel the bone fragments toward the proximal end.
This requires relatively complex manipulations and in particular demounting of the device, which does not guarantee satisfactory hygiene. Moreover, there is no provision for replacing the filter conveniently and satisfactorily in the device to carry out a plurality of successive bone recovery operations on the same patient. The recovery capacity is therefore limited.